1. Field of the Invention
The present invention relates to a radiation imaging system, a method for radiation imaging system, and a computer-readable storage medium that digitize captured radiation images by A/D conversion and send the digitized radiation image data via a wireless communication apparatus.
2. Description of the Related Art
There is available a digital radiation imaging apparatus which digitizes the radiation image captured by the apparatus and generates a sharper radiation image by processing the digitized radiation image. When a plurality of wireless digital X-ray imaging apparatuses are simultaneously operated in a hospital or the like in practice, wireless communication interference between X-ray rooms may hinder the implementation of desired communication performance. Interference between networks based on wireless communication is generally avoided by changing the frequency band used for wireless communication.
As a method to change the radio settings in a radiation sensor apparatus, for example, an X-ray sensor apparatus, a method using a wireless itself is available. For example, according to a wireless LAN standard complying with IEEE802.11, a client (CA) which tries to connect to an access point (AP) has a function of searching for a channel on which the AP exists by performing scanning while dynamically switching its operating frequency bands. Using this function allows to automatically connect to APs set on different channels in the respective X-ray rooms. In this case, however, the CA automatically connects to any AP within the radio range, and hence cannot selectively connect to one of synchronous access points existing in the respective X-ray rooms. Accordingly, it is difficult to perform control in order to synchronize an X-ray sensor apparatus with the desired radiation generator.
On the other hand, the wireless LAN standard covers an encryption function that conceals wireless communication. This function allows a wireless network to be created in each X-ray room by setting an encryption key used for wireless communication between a synchronous access point existing in a given X-ray room and an X-ray sensor apparatus and setting different encryption keys in the respective X-ray rooms. There is an invention configured, in consideration of the above situation, such that an AP and a CA respectively include two types of different wireless communication units to communicate security information such as encryption key information used by the first wireless communication unit via the second wireless communication unit capable of only short range communication (see Japanese Patent Laid-Open No. 2006-197063). A CA can participate in a wireless LAN via an AP which is accessible to the CA.
However, while a CA can participate in a particular wireless LAN in the method disclosed in Japanese Patent Laid-Open No. 2006-197063, in cases wherein there are a plurality of X-ray sensor apparatuses in one or more X-ray rooms or wherein an X-ray apparatus is moved between X-ray rooms, it is difficult to perform control in order to synchronize by wireless communication an X-ray sensor apparatus with the desired radiation generator.
Assume that in an environment in which wireless communication interference occurs, security settings are made by the method disclosed in Japanese Patent Laid-Open No. 2006-197063. In this case, while the X-ray sensor apparatus is linked with a synchronous access point in another X-ray room, the X-ray sensor apparatus may start security setting processing. In such a case, since no encryption key information match is found, the X-ray sensor apparatus discards the existing wireless LAN link and re-connects to a synchronous access point existing on another channel upon scanning. This disadvantageously prolongs the wait time for connection to a network.
As described above, it is difficult to simply and easily create a dedicated wireless LAN network, for each of a plurality of radiation rooms which cause mutual radio interference, between a synchronous access point capable of being connected to a radiation generator and a radiation sensor apparatus existing in a radiation room.
It is also difficult to connect radiation sensor apparatuses to desired wireless networks with a simple and intuitive operation when using the apparatuses while moving and interchanging them between a plurality of radiation rooms.